This invention relates to polyurethane-backed textiles, and particularly to textiles which are backed with a polyurethane foam.
Various textiles, most notably carpet, often have an attached polyurethane foam backing for cushioning and other purposes. These polyurethane-backed textiles are usually prepared by applying to one surface of the textile a mixture of polyisocyanate and at least one high equivalent weight polyol, which subsequently reacts to form a cellular backing adherent to the textile.
Preparing the backed textiles in this manner has met with formidable processing difficulties. As all of the reactive components of the polyurethane-forming composition are mixed prior to application to the textile, the initial reactivity must be delayed so that the composition does not gel before it is applied and gauged. The characteristics of the composition must also be such that it can easily be blown or frothed to a desirable density. Once the composition is blown or frothed and applied to the carpet, it must react quickly and completely in order to form a tack-free backing in as short a cure time as possible. In addition, the resulting polyurethane backing must have good physical properties, particularly good tensile, elongation and tear properties, low residual tack and high dimensional stability. Often, modifications in a polyurethane-forming composition which improve one of these processing characteristics of physical properties make others worse. Thus, it has been very difficult to provide a polyurethane-forming composition which has all of the desired attributes in processing and physical properties.
Accordingly, it would be desirable to provide a process for preparing polyurethane-backed textiles, wherein a polyurethane-forming composition is employed which is improved processing characteristics and/or physical properties.